In recent years, card connectors for electronic devices such as a cellular telephone have been known, in which a memory card, a function expansion card or any other similar card (hereinafter simply referred to as an “IC card”) incorporating an integrated circuit is inserted in order to electrically connect the IC card to the electronic device. The card connectors are facing demands for a smaller size and a thinner profile as well as demands for higher speed transmission of signals between the electronic device and the IC card and for a larger capacity of a memory. Power consumption is increased as a result of the higher speed transmission and the larger capacity of the memory. Accordingly, the IC card itself generates heat, thereby causing expansion, deformation or damage of the IC card itself which is formed by molding, electrical connection failures between external contact points of the IC card and contacts of the card connector. For this reason, as disclosed in Patent Literature 1, there is known a card heat dissipating mechanism designed for absorbing heat generated from an IC card. The mechanism is configured to cause a heatsink to contact an IC card being attached to a card connector to dissipate the heat from the IC card and thereby to maintain the IC card at a predetermined temperature or below.